Redash — Open Source Data Visualization & Dashboard Tool

What Redash Does

• SQL Editor: Full-featured SQL editor with schema browser, autocomplete, and query history
• 50+ Data Sources: PostgreSQL, MySQL, BigQuery, Snowflake, Redshift, ClickHouse, MongoDB, APIs, and more
• Visualizations: Charts, tables, maps, pivot tables, word clouds, and more from query results
• Dashboards: Compose visualizations into interactive dashboards with filters and parameters
• Alerts: Automated alerts when query results match conditions (email, Slack, webhook)
• Scheduled Queries: Auto-refresh queries on a schedule (hourly, daily, weekly)
• Sharing: Share queries and dashboards with team via links or embedding
• API: Full REST API for programmatic access to queries and results
• Parameters: Parameterized queries for dynamic, interactive dashboards

Architecture

┌──────────────┐     ┌──────────────┐     ┌──────────────┐
│  Browser     │────▶│  Redash      │────▶│  Your Data   │
│  Dashboard   │     │  Server      │     │  PostgreSQL  │
└──────────────┘     │  (Python/    │     │  MySQL       │
                     │   Flask)     │     │  BigQuery    │
                     └──────┬───────┘     │  Snowflake   │
                            │             │  ClickHouse  │
                     ┌──────┴───────┐     │  50+ more    │
                     │  Redis +     │     └──────────────┘
                     │  PostgreSQL  │
                     │  (Metadata)  │
                     └──────────────┘

Self-Hosting

Docker Compose

services:
  redash:
    image: redash/redash:latest
    command: server
    ports:
      - "5000:5000"
    environment:
      REDASH_DATABASE_URL: postgresql://redash:redash@postgres/redash
      REDASH_REDIS_URL: redis://redis:6379/0
      REDASH_SECRET_KEY: your-secret-key
    depends_on:
      - postgres
      - redis

  worker:
    image: redash/redash:latest
    command: worker
    environment:
      REDASH_DATABASE_URL: postgresql://redash:redash@postgres/redash
      REDASH_REDIS_URL: redis://redis:6379/0

  scheduler:
    image: redash/redash:latest
    command: scheduler
    environment:
      REDASH_DATABASE_URL: postgresql://redash:redash@postgres/redash
      REDASH_REDIS_URL: redis://redis:6379/0

  postgres:
    image: postgres:16-alpine
    environment:
      POSTGRES_USER: redash
      POSTGRES_PASSWORD: redash
      POSTGRES_DB: redash
    volumes:
      - pg-data:/var/lib/postgresql/data

  redis:
    image: redis:7-alpine

volumes:
  pg-data:

Key Features

Parameterized Queries

-- Parameters appear as {{param_name}} in queries
SELECT
  date_trunc('{{period}}', created_at) as period,
  COUNT(*) as orders,
  SUM(total) as revenue
FROM orders
WHERE created_at BETWEEN '{{start_date}}' AND '{{end_date}}'
  AND status = '{{status}}'
GROUP BY 1
ORDER BY 1

-- Parameters become dropdown/date picker controls in the dashboard
-- period: day, week, month (dropdown)
-- start_date, end_date: date pickers
-- status: completed, pending, cancelled (dropdown from query)

Visualization Types

Scheduled Queries & Alerts

Query: "Daily Active Users"
Schedule: Every day at 8am
Alert: When result < 1000
  → Send to Slack #metrics
  → Email to team@company.com

Query Snippets

-- Save reusable SQL snippets
-- Snippet: "date_filter"
WHERE created_at BETWEEN '{{start_date}}' AND '{{end_date}}'

-- Snippet: "user_join"
LEFT JOIN users u ON u.id = t.user_id

-- Use with trigger keyword in SQL editor

Redash vs Alternatives

FAQ

Q: Redash or Metabase — which should I choose? A: If your team is comfortable writing SQL, Redash feels more natural. If non-technical users need to explore data on their own, Metabase's visual query builder is friendlier. Both can be self-hosted for free.

Q: Is Redash still actively maintained? A: After Databricks acquired Redash, official development slowed down, but the community is still actively maintaining it (merging PRs and fixing bugs). For new projects, Metabase or Apache Superset are also worth considering.

Q: Can I visualize data from APIs? A: Yes. Redash supports JSON APIs and Python scripts as data sources. You can write Python code to call any API and return the results for visualization.

Sources & Credits

• GitHub: getredash/redash — 28.3K+ ⭐ | BSD-2-Clause
• Website: redash.io